Louw, C.W., E. Kemeny, J. Henning, J. van Niekerk, and C. Vleggaar. 1982. “THE HAZARDOUS GASEOUS AND VOLATILE CONSTITUENTS WHICH CURRENTLY ACCOMPANY THE PARTICULATES IN THE MAJOR SOUTH AFRICAN URBAN INDUSTRIAL CENTRES”. Clean Air Journal 6 (1): 10-19. https://doi.org/10.17159/caj/1982/6/1.7369.